To those who prefer paper maps, go at it. I don't drive my kitchen table. I don't have the paper map storage capacity for every state, every county, every town in the country in my door pocket. None of them can be retrieved to any degree of detail wanted with a couple of clicks & a roll of the mouse wheel or pinching of fingers on a screen.
If you are a weekend warrior you probably don't need anything at all. If you are the annual 2 week vacation traveler a phone or simple GPS will do. If you are a multi month wanderer covering thousands of miles & not really interested in a most direct route from one place to another, & maybe not even sure where the end of the day may find you, you want to have plenty of information at your fingertips & you don't want to have to rely on the internet to get it.
If all else fails I do have an old Walmart US/Canada atlas in a seat back pocket.